Method of conducting a transaction using an nfc device

ABSTRACT

The invention relates to a method of conducting a transaction between an NFC device and a contactless integrated circuit of the passive reader type. The method includes providing, in the contactless integrated circuit, at least one reader application emulation program and, by an intermediary unit of the NFC device, establishing a communication with the contactless integrated circuit, receiving from the contactless integrated circuit reader application commands and transferring the commands to the first host processor, and receiving card application responses supplied by the first host processor and transferring the responses to the contactless integrated circuit.

BACKGROUND OF THE INVENTION

Embodiments of the present invention relate to contactless transactionsconducted using a Near Field Communication (NFC) controller coupled toat least one host processor.

NFC technology is currently being developed by an industrial consortiumgrouped under the name “NFC Forum” (http://www.nfc-forum.org). NFCtechnology is derived from Radio Frequency Identification (RFID)technology and uses NFC controllers having several operating modes, inparticular a Reader mode and a Card Emulation mode.

FIG. 1 shows an NFC device generally termed “NFC chipset” including anNFC controller NFCC and at least one host processor HP1 linked to thecontroller NFCC by a bus BS1, for example of the Single Wire Protocol(SWP) type. The host processor may take the form of an integratedcircuit designated Universal Integrated Circuit Card (UICC), such as aSubscriber Identity Module (SIM) card. The host processor may also bethe baseband processor of a mobile telephone (that is, the processor incharge of telephonic communications). The resources of the controllerNFCC are available to the host processor HP1 to allow it to managecontactless applications. The controller NFCC includes a host controllerHC and a contactless interface CLF (“Contactless Front End Interface”)equipped with an antenna coil AC1. In practice, the host controller HCand the interface CLF may be made on the same semiconductor chip, suchas the MicroRead® chip commercialized by the applicant, or may be twodistinct chips, such as the chips “PicoRead® Microcontroller” and“PicoRead® RF Interface” commercialized by the applicant.

The interface CLF of the controller NFCC can generally operate accordingto several RF technologies designated RFTi in FIG. 1, for example “TypeA” or “Type B”, such as defined by ISO/IEC 14443 parts 2, 3, and 4;“Type B”, such as defined by ISO/IEC 14443-2 with a standard framingsuch as defined by ISO/IEC 14443-3; and “Type F”, such as defined by ISO18092 in passive mode at 212 and 424 kilo octets per second (kops), orby the Japanese Industrial Standard JIS X 6319-4. Each RF technology, orcontactless communication protocol, defines an emission frequency of themagnetic field, a method of modulating the magnetic field to transmitdata in active mode, a method of charge modulation to transmit data inpassive mode, a method of data coding, a data frame format, and thelike.

Due to its wide communication capabilities, such an NFC device isgenerally integrated in a portable device HD (“Handheld Device”) such asa mobile telephone, a Personal Digital Assistant (PDA), or the like.Application examples of the NFC device are shown in FIG. 2, which showsa portable device HD equipped with the NFC device of FIG. 1, the deviceHD of FIG. 2 is in the form of a mobile telephone. Reader ApplicationsRAP and Card Applications CAP may be distinguished.

Reader Applications (RAP)

The controller NFCC operates as an NFC reader to conduct a transactionwith a Contactless Integrated Circuit CIC. A reader application RAPi isexecuted by the host processor HP1 (FIG. 1). The host processor HP1 setsthe interface CLF in an active operating mode where it emits a magneticfield FLD, sends data by modulation of the magnetic field, and receivesdata by charge modulation and inductive coupling. This type ofapplication may be free (for example, reading a tag containing the busschedules at a bus stop) and may be executed by an unsecure processor.The host processor HP1 may, in this case, be the baseband processor ofthe mobile telephone. If it is a paid application, the host processorHP1 is preferably a secure processor (for example, a processor of a SIMcard), because the access to the service requires an identification ofthe subscriber.

Card Applications (CAP)

The operating principle of the card emulation mode is described by thepatent EP 1 327 222 (U.S. Pat. No. 7,098,770) in the name of theapplicant. A card application (CAPi) is executed by the host processorHP1 (FIG. 1). The host processor HP1 sets the controller NFCC in apassive operating mode and forms, with the controller NFCC, theequivalent of a contactless integrated circuit, which is seen by areader RD as a contactless card. Thus, the controller NFCC does not emita magnetic field, receives data by demodulating a magnetic field FLDemitted by the reader RD, and emits data by modulating the impedance ofits antenna circuit (charge modulation). The related applications aregenerally applications for payment or payment access control (paymentmachine, subway entrance, or the like.). The portable device HD istherefore used in this case as a chip card. This type of application ismost often secure, and the host processor HP1 that executes theapplication program is in this case a secure processor, for example aSIM card processor.

Standardized Architecture of an NFC Device

Inside the NFC device, the bus BS1 generally supports communicationinterfaces called HCI (“Host Controller Interface”) by the intermediaryof the controller NFCC and the host processor HP1 exchanging data inconformance with the Host Controller Protocol HCP. This protocolprovides a routing of data according to routing channels called “pipes”described in the applications EP 1 855 229 (US 2007/0263595) or EP 1 855389 (US 2007/0263596) in the name of the applicant.

The HCI interface and the HCP protocol are also described in theEuropean Telecommunications Standards Institute's ETSI TS 102 622specification entitled “Smart Cards; Universal Integrated Circuit Card(UICC); Contactless Front-end (CLF) interface; Host Controller Interface(HCI)”. In addition, the commands and the responses to commandsexchanged during a transaction between the host processor HP1 and anexternal device, such as the passive contactless integrated circuit CICor the reader RD, are defined by the NFCForum-TS-Type-4-Tagspecifications entitled “Type 4 Tag Operation”. Equally, the format ofdata exchanged during an NFC transaction is defined by theNFCForum-TS-NDEF specifications entitled “NFC Data Exchange Format(NDEF)”.

As shown in FIG. 1, these diverse specifications define an NFC devicearchitecture wherein the controller NFCC executes one or more RFTitechnologies (operating modes of the interface CLF, for example Type A,Type B, Type B′, and Type F), whereas the host processor HP1 executesreader applications RAPi and card applications CAPi. Each technologyRFTi is accessible by the intermediary of a Reader RF Gate RRFG or by aCard RF Gate CRFG. Each reader application RAPi includes a ReaderApplication Gate RAG that is connected by the intermediary of a pipe toa reader RF gate RRFG associated with a technology RFTi. Similarly, eachcard application CAPi comprises a Card Application Gate CAG that isconnected by the intermediary of a pipe to a card RF gate CRFGassociated with a technology RFTi. With each reader gate RRFG or cardgate CRFG is associated a registry that contains parameters necessaryfor the management of the RF channel according to the technology RFTithat the reader application or the card application uses.

Commands Exchanged During the Execution of a Reader Application

During the execution of a reader application RAPi, the host processorHP1 configures the interface CLF in active mode by the intermediary of areader application gate RAG. The reader application RAPi activates agate RAG and requests the HCI administrator (software unit executed bythe controller NFCC) to open a pipe P1 between the gate RAG and a gateRRFG associated with a desired technology RFTi. The application RAPithen emits commands CAPDU that are transmitted to the controller NFCC bythe intermediary of the pipe P1, then are transmitted to the integratedcircuit CIC by the intermediary of an RF channel. The contactlessintegrated circuit CIC sends back responses RAPDU to the controllerNFCC, which the controller NFCC then transmits to the host processor HP1via the intermediary of the pipe P1.

Commands Exchanged During the Execution of a Card Application

During the execution of a card application CAPi, the host processor HP1emulates a passive contactless card and uses the interface CLF inpassive mode. The card application CAPi activates a gate CAG andrequests the HCI administrator to open a pipe P2 between the gate CAGand a gate CRFG associated with a desired technology RFTi. The reader RDsends to the controller NFCC commands CAPDU that the controller NFCCtransmits to the host processor HP1 by the intermediary of the pipe P2.The host processor HP1 emits responses RAPDU that are transmitted to thecontroller NFCC via the intermediary of the pipe P2. The responses arethen transmitted by the controller NFCC to the reader RD, by theintermediary of an RF channel.

The commands CAPDU and the responses RAPDU (generally designated“C-APDU” and “R-APDU”) are defined by the standard ISO 7816-4 and aredetailed at point 5 of the “Type 4 Tag Operation” specification.

In summary, the host processor HP1 emits commands CAPDU when operatingin reader mode and conducts a transaction with a contactless integratedcircuit CIC, and the contactless integrated circuit CIC sends backresponses RAPDU to the host processor HP1. Inversely, when operating incard emulation mode, the host processor HP1 receives commands CAPDUemitted by a reader RD and sends back responses RAPDU to the reader RD.

It is known that the development of NFC technology is closely linked tothe development of applications of the card emulation type, which allowfor the use of a portable device HD as a contactless chip card. Eventhough infrastructures equipped with NFC readers already exist, inparticular in the domain of access control, these infrastructures arerare and are not developing at a sufficient rate to allow for thedesired development of NFC technology. In particular, a constraint thatis impeding the development of NFC infrastructures is the cost of NFCreaders themselves, as well as the cost of their installation in theapplication areas. As a reader is an active device that emits a magneticfield, it presents a certain complexity and non-negligible cost, andmust be linked to an electrical power supply.

It may therefore be desired to provide a method of conducting an NFCtransaction and an NFC system that allows for the implementation of cardapplications without the constraint of requiring the installation of agroup of readers.

BRIEF SUMMARY OF THE INVENTION

The present invention includes the observation that, during atransaction in card emulation mode, the NFC controller does not use theresources of the contactless interface CLF for the emission of amagnetic field. It may therefore be considered that a transactionconducted between an NFC reader in active mode and an NFC controller inpassive mode represents a “waste” of resources, because each of thesetwo elements has the capability of emitting a magnetic field, but thoseof the NFC controller not being used.

Based on this observation, embodiments of the invention relate to amethod of conducting a transaction between an NFC device and a passivecontactless integrated circuit. The NFC device includes an NFCcontroller coupled to a contactless communication interface, and atleast a first host processor comprising at least one card applicationprogram. The method includes: providing, in the contactless integratedcircuit, at least one reader application emulation program configured tosupply first reader application commands and to treat first cardapplication responses; setting, by means of an intermediary unit of theNFC device, the contactless communication interface in an active mode toemit a magnetic field and establish a communication with the contactlessintegrated circuit; receiving, from the contactless integrated circuit,first reader application commands and transferring them to the firsthost processor; and receiving, from the first host processor, first cardapplication responses and transferring them to the contactlessintegrated circuit.

In one embodiment, the method includes: providing, in the intermediaryunit, a first protocol inversion program; providing, in the contactlessintegrated circuit, a second protocol inversion program configured tocooperate with the reader application emulation program; establishing,between the first and the second inversion programs, a contactlesscommunication wherein the intermediary unit acts as a reader relative tothe contactless integrated circuit; and, by the intermediary of thesecond and the first inversion programs, transferring to the first hostprocessor, first reader application commands supplied by the readerapplication emulation program; and transferring to the readerapplication emulation program, first card application responses suppliedby the card application of the first host processor.

In one embodiment, the method includes the following steps, conducted bythe intermediary unit: receiving, from the first host processor, firstcard application responses, encapsulating the responses in second readerapplication commands, and transferring the second reader applicationcommands to the contactless integrated circuit; and receiving from thecontactless integrated circuit first reader application commandsencapsulated in second card application responses, de-encapsulating thefirst reader application commands, and transferring the de-encapsulatedcommands to the first host processor.

In one embodiment, the first reader application commands emitted by thereader application emulation program and the first card applicationresponses emitted by the card application program are in the APDU ISO7816 format.

In one embodiment, the second reader application commands and the secondcard application responses are in the APDU ISO 7816 format.

In one embodiment, the method includes supplying to the first hostprocessor, via the intermediary unit, HCI interface commands that causethe first host processor to perceive the first reader applicationcommands received from the contactless integrated circuit as having beenemitted by an NFC reader in the active mode.

In one embodiment, the method includes recording in a registry at thedisposal of the first host processor, RF channel parameters that causethe first host processor to perceive the first reader applicationcommands received from the contactless integrated circuit as having beenemitted by an NFC reader in the active mode.

In one embodiment, the intermediary unit is a host controller of the NFCdevice.

In one embodiment, the intermediary unit is a second host processor ofthe NFC device.

Embodiments of the invention also relate to a contactless integratedcircuit of the passive type arranged, or to be arranged on or within afixed or portable support. The integrated circuit includes an NFC readeremulation program, and being configured to supply first readerapplication commands and to treat first card application responsesreceived in response to reader application commands.

In one embodiment, the integrated circuit includes a protocol inversionprogram configured to respond to second reader application commands andto supply second card application responses, and at least one readerapplication emulation program configured to supply the first readerapplication commands and to treat the first card application responses.

In one embodiment, the integrated circuit is configured to receive firstcard application responses encapsulated in second reader applicationcommands, and to encapsulate, in second card application responses,first reader application commands.

In one embodiment, the integrated circuit is configured to receive firstcard application responses and second reader application commands in theAPDU ISO 7816 format, and to emit first reader application commands andsecond card application responses in the APDU ISO 7816 format.

Embodiments of the invention also relate to an NFC device including anNFC controller coupled to a contactless communication interface. A firsthost processor includes at least one card application program and isconfigured to treat first reader application commands and to supplyfirst card application response. An intermediary unit coordinates atransaction between the host processor and a passive contactlessintegrated circuit of the reader type. The intermediary unit isconfigured to: set the contactless communication interface in an activemode where a magnetic field is emitted; receive, via the intermediary ofthe contactless communication interface in active mode, first readerapplication commands emitted by a passive contactless integrated circuitof the reader type and transfer the commands to the first hostprocessor; and receive first card application responses supplied by thefirst host processor and transfer the responses, via the intermediary ofthe contactless communication interface in active mode, to the passivecontactless integrated circuit of the reader type.

In one embodiment, the intermediary unit is also configured to emit, viathe intermediary of the contactless communication interface, secondreader application commands allowing for the management of acommunication with a passive contactless integrated circuit of thereader type; and to receive, by the intermediary of the contactlesscommunication interface, second card application responses emitted by apassive contactless integrated circuit of the reader type.

In one embodiment, the intermediary unit is configured to encapsulate,in second reader application commands, first card application responsessupplied by the first host processor and transmit the second readerapplication commands via the intermediary of the contactlesscommunication interface; and to receive, by the intermediary of thecontactless communication interface, second card application responseswithin which are encapsulated first reader application commands,de-encapsulate the first reader application commands, and transfer thede-encapsulated commands to the first host processor.

In one embodiment, the intermediary unit is configured to transmit, viathe intermediary of the contactless communication interface, secondreader application commands and first card application responses in theAPDU ISO 7816 format; and to receive, via the intermediary of thecontactless communication interface, second card application responsesand first reader application commands in the APDU ISO 7816 format.

In one embodiment, the intermediary unit is also configured to supply,to the first host processor, HCI interface commands that cause the firsthost processor to perceive that the first reader application commandsreceived from a contactless integrated circuit as having been emitted byan NFC reader in the active mode.

In one embodiment, the intermediary unit is also configured to supply,to the first host processor, RF channel parameters that cause the firsthost processor to perceive reader application commands received from acontactless integrated circuit as having been emitted by an NFC readerin the active mode.

In one embodiment, the intermediary unit is a host controller of the NFCdevice.

In one embodiment, the intermediary unit is a second host processor ofthe NFC device.

Embodiments of the invention also relate to a portable device, includingan NFC device according to the invention.

Embodiments of the invention also relate to a method of establishing acommunication with an NFC device. The NFC device includes an NFCcontroller coupled to a contactless communication interface. At least afirst host processor includes at least one card application program. Themethod includes: providing a contactless integrated circuit of thepassive type arranged or to be arranged on or within a fixed or portablesupport; and configuring the contactless integrated circuit to supplythe NFC controller with first reader application commands and treatfirst card application responses received from the NFC controller inresponse to reader application commands.

In one embodiment, the method comprises includes, in the contactlessintegrated circuit: a protocol inversion program configured to respondto second reader application commands from the NFC device and to supplythe NFC device with second card application responses; and at least onereader application emulation program configured to supply the firstreader application commands and to treat the first card applicationresponses.

In one embodiment, the method includes: with the contactless integratedcircuit, receiving first card application responses encapsulated insecond reader application commands; and with the contactless integratedcircuit, encapsulating, in second card application responses, firstreader application commands.

In one embodiment, first card application responses, second readerapplication commands, first reader application commands and second cardapplication responses are in the APDU ISO 7816 format.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofthe invention, will be better understood when read in conjunction withthe appended drawings. For the purpose of illustrating the invention,there are shown in the drawings embodiments which are presentlypreferred. It should be understood, however, that the invention is notlimited to the precise arrangements and instrumentalities shown.

In the drawings:

FIG. 1 shows the architecture of a conventional NFC device;

FIG. 2 shows applications of the NFC device;

FIG. 3 shows steps of a conventional transaction between the NFC deviceof FIG. 1 and an external NFC reader;

FIG. 4 shows steps of a conventional transaction between the NFC deviceof FIG. 1 in reader mode and a contactless integrated circuit;

FIG. 5 shows the architecture of an NFC device according to anembodiment of the invention;

FIG. 6 shows applications of the NFC device of FIG. 5;

FIG. 7 shows a transaction between the NFC device of FIG. 5 and apassive reader according to an embodiment of the invention;

FIG. 8 shows steps of a transaction between the NFC device of FIG. 5 anda passive reader according to an embodiment of the invention;

FIG. 9 shows the architecture of another embodiment of an NFC deviceaccording to an embodiment of the invention;

FIG. 10 shows a transaction between the NFC device of FIG. 9 and apassive reader according to the invention; and

FIG. 11 shows steps of a transaction between the NFC device of FIG. 9and a passive reader according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 3 shows steps of a conventional transaction between the NFC deviceof FIG. 1 and a reader RD. FIG. 4 shows steps of a conventionaltransaction between the NFC device of FIG. 1 and a contactlessintegrated circuit CIC. The steps shown in FIGS. 3 and 4 implementstandardized commands described by the specifications ETSI TS 102 622,NFCForum-TS-Type-4-Tag, and NFCForum-TS-NDEF.

Transaction in Card Emulation Mode

The transaction shown in FIG. 3 includes the following initializationsteps:

A pipe P1 is created and opened between a card application CAPi executedby the host processor HP1 and a technology RFTi executed by thecontroller NFCC, via the intermediary of a card application gate CAG anda card RF gate CRFG (step “PIPE_CREATE, PIPE_OPEN”);

The controller NFCC detects the magnetic field emitted by the reader RDand sends a command EVT_FIELD_ON to the processor HP1;

The controller NFCC conducts initialization steps of a communicationwith the reader RD with the creation of an RF communication channel, aswell as anti-collision steps if other NFC devices or contactless cardsare found in the interrogation field of the reader RD (step “INIT,ANTICOL”);

When the connection with the reader RD is established, the controllerNFCC sends a command EVT_CARD_ACTIVATED to the host processor HP1 toindicate to the host processor HP1 that a transaction may begin;

The transaction as such then includes the following steps:

The reader RD sends commands CAPDU, via the RF communication channel, tothe processor NFCC;

The controller NFCC transmits these commands, via the intermediary ofthe pipe P1 and in an encapsulated form in commands EVT_SEND_DATA(command of the “event” type of the set of commands of the interface HCIdefined by the ETSI specification), to the host processor HP1;

The card application CAPi of the host processor HP1 sends responsesRAPDU, via the pipe P1 and in an encapsulated form in commandsEVT_SEND_DATA, to the controller NFCC; and

The controller NFCC transmits responses RAPDU, via the RF channel, tothe reader RD.

A first command CAPDU emitted by the reader RD may be a selectioncommand of the card application CAPi that the host processor HP1executes, for example the command “Tag Application Select” defined atpoint 6.4.2 of the “Type 4 Tag Operation” specification:

CLA INS P1 P2 Lc Data Le 00h A4h 04h 00h 07h D2760000850100h —

The transaction may be interrupted if the host processor HP1 does notrespond by sending back the response SW1-SW2=9000h (hexadecimalnotation).

When the transaction is finished (or interrupted), the reader RD stopsemitting the magnetic field and the controller NFCC sends to the hostprocessor HP1 a command EVT_CARD_DEACTIVATED for the deactivation of thecard application and a command EVT_FIELD_OFF indicating that themagnetic field is no longer present. The pipe P1 is then closed (step“PIPE_CLOSE”).

Transaction in Reader Mode

The transaction shown in FIG. 4 includes the following initializationsteps:

A pipe P2 is created and opened between a reader application RAPi of thehost processor HP1 and a technology RFTi of the controller NFCC, via theintermediary of a reader application gate RAG and of a reader RF gateRRFG (steps “PIPE_CREATE, PIPE_OPEN”);

The reader application RAPi sends, at regular intervals, interrogationcommands EVT_READER_REQUESTED aiming to detect the presence of thecontactless integrated circuit CIC (interrogation method called“polling”) to the controller NFCC;

When the contactless integrated circuit CIC is detected, the controllerNFCC conducts initialization steps “INIT, ANTICOL” of a communicationwith the contactless integrated circuit CIC with the creation of an RFcommunication channel, and optionally anti-collision steps (if othercontactless integrated circuits are present in the field);

The controller NFCC sends the command EVT_TARGET_DISCOVERED to the hostprocessor HP1 to indicate to the host processor HP1 that a transactioncan begin.

The transaction as such then includes the following steps:

The host processor HP1 sends, via the pipe P2, commands CAPDUencapsulated in commands WR_XCHG_DATA to the controller NFCC;

The controller NFCC transmits, by the intermediary of the RF channel,commands CAPDU to the contactless integrated circuit CIC;

The contactless integrated circuit CIC sends responses RAPDU to thecontroller NFCC;

The controller NFCC transmits, via the pipe P2, responses RAPDUencapsulated in commands WR_XCHG_DATA to the host processor HP1.

As previously, a first command CAPDU emitted by the host processor HP1may be a selection command of the application that the integratedcircuit CIC executes, for example the command described above. Thetransaction may be interrupted if the contactless integrated circuit CICdoes not respond by sending back the response SW1-SW2=9000h (hexadecimalnotation), which signifies that it does not comprise an applicationcorresponding to the reader application that the host processor HP1executes.

When the transaction is finished (or interrupted), the host processorHP1 sends a command EVT_END_OPERATION for closing the RF channel to thecontroller NFCC, and the pipe P2 is then closed (step “PIPE_CLOSE”).

The commands CAPDU and the responses RAPDU (usually designated “C-APDU”and “R-APDU”) are defined by the ISO 7816-4 standard. Their format isdetailed at point 5 of the “Type 4 Tag Operation” specification(NFCForum-TS-Type-4-Tag). The commands CAPDU recommended by thesespecifications are the commands Select, ReadBinary, UpdateBinary, forexample “Tag Application Select”, “Capability Container Select”, “NDEFSelect”, “Capability Container Read”, “NDEF Read”, “NDEF Update”.

The conventional transactions of the type described above thus define apassive contactless integrated circuit as an element configured to treatcommands CAPDU emitted by a reader and to supply responses RAPDU toreader application commands.

Examples of Transactions According to Embodiments of the Invention andCorresponding NFC Device Architectures

An NFC transaction process according to embodiments of the inventionprovides a passive contactless integrated circuit of the reader RCICtype, designated for convenience as “passive contactless integratedcircuit of reader type” or “passive reader” because it forms theequivalent of a reader not emitting a magnetic field. Such a passivereader is configured to supply commands of the reader type and to treatresponses emitted by a host processor in card emulation mode. It isgenerally in the form of an integrated circuit with a microprocessor ormicrocontroller equipped with a contactless communication interface, aprogram memory (read only memory), and a data memory (random accessmemory), and offering a sufficient calculation capacity to emulate theoperation of a reader.

An embodiment of the method according to the invention equally providesan NFC device architecture that is designed to allow a host processor ofthe device configured in the card emulation mode to conduct atransaction with such a passive reader.

FIG. 5 shows an embodiment of such an NFC device architecture. The NFCdevice is susceptible of being integrated in a portable device HD suchas a mobile telephone, a PDA, an active card called “sticker” (card tobe glued on the back of a mobile telephone), a protective mobiletelephone envelope (“skin”), or the like. The NFC device includes acontroller NFCC and at least one host processor HP1 linked to thecontroller NFCC by a data bus BS1, for example of the Single WireProtocol SWP type. The controller NFCC includes a contactless interfaceCLF equipped with an antenna coil AC1, and a host controller HC. It willbe assumed here, in a non-limiting manner, that the controller NFCCpresents all the functionalities of a conventional NFC controller, inparticular that it implements one or more RF technologies RFTi, and thatit is configured to activate a reader RF gate RRFG or a card RF gateCRFG1 to allow the host processor HP1 to execute reader applicationsRAPi and card applications CAPi by using these RF technologies. It willalso be assumed that the host processor HP1 includes at least one cardapplication CAPi, at least one reader application RAPi, a cardapplication gate CAG for the card application CAPi, and a readerapplication gate RAG for the reader application RAPi. Thus, the NFCdevice may conduct a transaction with a conventional contactlessintegrated circuit CIC by opening a pipe P1 between the readerapplication RAPi and a technology RFTi, via the intermediary of gatesRAG and RRFG. The NFC device may also conduct a transaction with aconventional reader RD by opening a pipe P2 between the card applicationCAPi and a technology RFTi, via the intermediary of gates CAG and CRFG1.

The NFCC device also includes a functionality PINVP1 that will be calledin the following “protocol inversion program” or “inversion program”.The inversion program PINVP1 is executed here by the host controller HCof the controller NFCC and is provided to establish a communication witha passive reader RCIC according to the invention, via the intermediaryof a technology RFTi and the interface CLF. The inversion program PINVP1is also configured to activate a card RF gate CRFG2 and to request theadministrator HCI to open a pipe P3 linking the gate CRFG2 to a gate CAGof a card application CAPi of the host processor HP1, in order totransmit to the host processor HP1 commands supplied by the passivereader RCIC as if they were commands received from a true NFC reader orequivalent device, in particular another NFC device operating in readermode. The inversion program PINVP1 is equally configured to receive fromthe host processor HP1 responses to such commands, and to transmit themto the passive reader RCIC.

Application examples of the NFC device according to the invention areshown in FIG. 6, which shows a portable device HD equipped with the NFCdevice of FIG. 5, the device HD being here a mobile telephone. Readerapplications RAP and card applications CAP of the types previouslydescribed in relation with FIG. 2 can be seen. Among the cardapplications CAP, a supplementary application according to the presentinvention can be seen, that is a transaction between the device HD1 anda passive reader RCIC.

In FIG. 6, the passive reader RCIC is shown as a chip connected to anantenna coil AC2. This ensemble, chip and antenna coil, is susceptiblein practice of being integrated within or mounted on any type ofportable support. It may be for example in the form of an electronic“tag”, contactless card, or be directly integrated in any fixed support.

The advantage of such a passive reader RCIC is that it allows for theemulation of an NFC reader such as the reader RD shown in FIG. 5,without the inconveniencies related with the installation of a truereader. Thanks to the embodiments of the invention, it is thereforepossible to install, at minimum cost, a group of “virtual readers”formed by passive readers RCIC according to the invention.

In an embodiment of the invention, it is desired that the emulation ofan NFC reader by means of the passive reader RCIC is transparent for thehost processor HP1, in order to ensure the compatibility of theinvention with conventional host processors designed to dialogue in cardemulation mode with true NFC readers, in particular processors ofNFC-SIM cards recently commercialized and provided to be associated withan NFC controller as host processors. In such an embodiment, theinversion program PINVP1 is configured such that the host processor HP1perceives, during a transaction with the passive reader RCIC, that it isin the presence of a true reader.

FIG. 7 shows an architecture of the NFC device and of the passive readerRCIC designed to this end, and shows a card application CAPi of theprocessor HP1 conducting a transaction with the passive reader RCIC.Each element RCIC, NFCC, HP1 includes communication layers shown in theform of a physical layer PHL and a data link layer DLL. Each physicallayer PHL includes hardware and low-level protocol execution componentsfor the emission and the reception of data (modulation and demodulationof signals, coding and decoding of data, and the like). A physical layerPHLa of the passive reader RCIC cooperates with a first physical layerPHLb of the controller NFCC, that is to say the interface CLF, to createan RF communication channel and to ensure the transmission and thereception of data in the RF channel. A second physical layer PHLc of thecontroller NFCC cooperates with a physical layer PHLd of the hostprocessor HP1 to ensure the transmission of data on the bus BS1. Thephysical layers PHLc, PHLd are, for example, hardware components ofmanagement of an SWP bus and components of execution of a low-levelprotocol for the emission and the reception of data via the SWP bus.

Above the physical layers, a data link layer DLLa of the passive readerRCIC cooperates with a first data link layer DLLb of the controllerNFCC, to form a data link layer ensuring the transport of data in the RFchannel created by the physical layers PHLa and PHLb. The data linklayer protocol depends upon the technology RFTi that is activated forthe application during a transaction, for example Type A, Type B, TypeB′, or Type F, and is defined by the previously-mentionedspecifications. A second data link layer DLLc of the controller NFCCcooperates with a data link layer DLLd of the host processor HP1 to forma data link DLL2 ensuring the transport of data between the controllerNFCC and the host processor HP1. The layers DLLc, DLLd comprise forexample SWP data link layers and HCI data link layers. As defined by theETSI TS 102 622 specification, paragraph 4.1 FIG. 1, an HCI data linklayer includes, for example, an HCI administration layer, an HCP routinglayer (“HCP routing”), a message transport layer (“HCP messaging”), anda “gate layer” that includes the card application or reader applicationgates and the RF card and reader gates.

Finally, above the data link layers, the controller NFCC includes theinversion program PINVP1, the host processor HP1 includes at least onecard application CAPi, and the passive reader RCIC includes a protocolinversion program PINVP2 cooperating with a “Reader ApplicationEmulation Program” RAEP.

During a transaction with the passive reader RCIC, the inversion programPINVP1 configures the interface CLF in active mode to emit a magneticfield, allowing an RF channel to be established according to atechnology RFTi with the passive reader RCIC. The inversion programPINVP1 then dialogues with the inversion program PINVP2 of the passivereader RCIC and addresses to the passive reader RCIC commands CAPDU2. Itreceives responses RAPDU2 emitted by the inversion program PINVP2 inwhich are encapsulated the commands CAPDU1 supplied by the program RAEP,destined for the host processor HP1. The inversion program PINVP1de-encapsulates the commands CAPDU1 and communicates the commands CAPDU1to the card application CAPi of the host processor HP1 via an HCI pipeby means of HCI commands. The inversion program PINVP1 then receivesresponses RAPDU1 emitted by the card application CAPi of the hostprocessor HP1, via the HCI interface. It encapsulates them in commandsCAPDU2 that it sends to the passive reader RCIC via the RF channel. Theinversion program PINVP2 of the passive reader RCIC receives thesecommands, extracts from them the responses RAPDU1, and communicates themto the program RAEP for treatment, which then supplies a new commandCAPDU1 and so forth until the transaction is achieved.

A command CAPDU generally includes fields “CLA”, “INS”, “P1”, “P2”,“Lc”, “DATA”, “Le”. The field “DATA” is an optional data field. Theencapsulation of responses RAPDU1 in commands CAPDU2 is done by theinversion program PINVP1 by inserting the responses RAPDU1 in the datafield “DATA”. Similarly, a response RAPDU generally comprises fieldsDATA, SW1, SW2, the field “DATA” also being an optional data field. Theencapsulation of commands CAPDU1 in responses RAPDU2 is done by theinversion program PINVP2 by inserting these commands CAPDU1 in this datafield “DATA”.

The card application CAPi of the host processor HP1 thus receives, viathe HCI interface, commands CAPDU1 that appear to be emitted by an NFCreader, and sends to the “virtual” reader responses CAPDU1. In FIG. 7, alink in bold shows a virtual link that is established between the cardapplication CAPi of the host processor HP1 and the reader applicationemulation program RAEP of the passive reader RCIC, by the intermediaryof inversion programs PINVP1, PINVP2.

FIG. 8 describes, in more detail, steps of a transaction between thehost processor HP1 and the passive reader RCIC. This implementationexample of the invention is based on the ETSI TS 102 622 specificationin that it concerns the interface between the host processor HP1 and thecontroller NFCC.

A detection phase (DET) of the passive reader RCIC, a transactioninitialization phase (TINIT), a transaction phase as such (TRANSACTION),and an end of transaction phase (EOT) can be distinguished.

The detection phase (DET) aims to detect the presence of the passivereader RCIC. As it does not emit a field, it must be detected as aconventional contactless integrated circuit, before it may beascertained that it includes a reader application emulation programRAEP.

This preliminary detection phase may be implemented according to variousmethods. In one embodiment, the inversion program PINVP1 is permanentlyactive and regularly requests that the interface CLI emit the magneticfield to detect the presence of a contactless integrated circuit, thentries to determine whether this contactless integrated circuit is apassive reader or not. In another embodiment, the detection of thepassive reader RCIC is confided to a reader application RAPi situated inthe host processor HP1 or any other host processor susceptible of beinglinked to the controller NFCC. This second method will now be describedbecause it is in conformance with the NFC device architecture such asdefined by the previously-cited ETSI specification, according to whichthe controller NFCC emits the magnetic field in response to commandssupplied by host processors.

Detection Phase (DET)

It is assumed in the following that a reader application RAPi, executedhere by the host processor HP1, has been activated beforehand and islinked to the controller NFCC by the intermediary of gates RAG, RRFG andof a pipe P1 (Cf. FIG. 5). The application RAPi regularly polls thesurroundings of the NFC device by addressing to the controller NFCC thecommand EVT_READER_REQUESTED. When the passive reader RCIC is detected,the controller NFCC conducts initialization steps of an RF communicationchannel, optionally of anti-collision, and of activation of theintegrated circuit RCIC (steps “INIT, ANTICOL”). The controller NFCCthen sends to the application RAPi the command EVT_TARGET_DISCOVERED.The application RAPi then addresses the conventional applicationselection command “TagApplicationSelect” to the controller NFCC. Thecommand is emitted in the form of command CAPDU2(“CAPDU2[TagApplicationSelect]”) and is addressed to the controllerNFCC1, encapsulated in the command WR_XCHG_DATA. The command CAPDU2 istransferred by the controller NFCC to the passive reader RCIC via the RFchannel. The passive reader RCIC sends back a particular responseRAPDU2, containing an information “ReaderTagType” signifying that itforms a passive reader. This particular response differs fromconventional responses such as those defined by theNFCForum-TS-Type-4-Tag specification, table 3, section 5.2.2. Thisresponse may be a response without a data field containing a fieldSW1-SW2 different from that usually sent back by a contactlessintegrated circuit, for example the field SW1-SW2=9001h (hexadecimalnotation) instead of the field SW1-SW2=9000h. In another embodiment, theresponse contains a standard field SW1-SW2 with a value 9000h, but itcontains a determined data field signifying that the integrated circuitis of the passive reader type.

Transaction Initialization Phase (TINIT)

The particular response RAPDU2 causes the inversion program PINVP1 to beactivated by the controller NFCC. The inversion program PINVP1 thenactivates the card RF gate CRFG2 and generates an associated registrysuch as that described by ETSI TS 102 622 point 9.3.3.4. This volatileregistry contains parameters of the RF channel that the card applicationmust know. The creation and the utilization of this registry will not befurther described here and are within the purview of the skilled person.It will however be noted that the inversion program PINVP1 may store inthe registry RF channel parameters that do not correspond to those ofthe RF channel that was created by the controller NFCC to access thepassive reader RCIC. Thus, besides its NFC reader emulation function,the inversion program PINVP1 may allow for the emulation of an RFtechnology in relation to the card application CAPi, in particular ifthe application is not compatible with the RF technology of the passivereader RCIC.

For example, during the detection phase, the reader application RAPi mayhave detected the passive reader RCIC using type A protocol. However,the card application CAPi may be configured to dialogue with type Breaders. In one embodiment, the protocol inversion program PINVP1retrieves the protocol type supported by the card application CAPi fromthe NFCC controller registry. Then, the protocol inversion programPINVP1 embeds or encapsulates this information in a commandCAPDU2[RequestforCAPDU] described below, which is sent to the passivereader RCIC. Then, the reader application emulation program RAEP of thepassive reader RCIC uses type B protocol for communicating with the cardapplication CAPi, whereas the protocol inversion programs PINVP1 andPINVP2 continue to exchange data using the type A protocol. Therefore,the transport protocol used between the passive reader RCIC and thecontactless interface CLF of the controller NFCC is “transparent” forthe card application CAPi and the reader application emulation programRAEP.

Once the card RF gate CRFG2 has been activated, the inversion programPINVP1 requests the HCI administrator to open the pipe P3 between thegate CAG of the card application CAPi and the gate CRFG2 (steps“PIPE_CREATE, PIPE_OPEN”). The inversion program then sends the commandEVT_FIELD_ON to the card application CAPi to make it believe that an NFCreader emitting a magnetic field has been detected.

The initialization phase then comprises the sending, by the inversionprogram PINVP1, of a command CAPDU2 of the type CAPDU2[RequestforCAPDU]forming a request for the supply of a first reader application commandCAPDU1. The passive reader RCIC responds for example by means of aresponse of the type RAPDU2(CAPDU1[SelAppX]), within which isencapsulated a command CAPDU1 that designates the application “X” toselect (“SelAppX”). Upon reception of the response RAPDU2, the inversionprogram PINVP1 de-encapsulates the command CAPDU1, addresses to the cardapplication CAPi the command EVT_CARD_ACTIVATED that signifies that theapplication should become active, then address to it the commandCAPDU1[SelAppX] encapsulated in the command “EVT_SEND_DATA”.

Transaction Phase (TRANSACTION)

The transaction phase as described above in relation with FIG. 7. Itcomprises the exchange of commands CAPDU1 and of responses RAPDU1between the card application CAPi and the reader application emulationprogram RAEP. More precisely, in response to the command CAPDU1[SelAppX]received at the end of the initialization phase, the card applicationCAPi sends back a first response RAPDU1, then the program RAEP sendsback a command CAPDU1, and so forth until the end of the transaction.The commands CAPDU1 and the responses RAPDU1 are respectivelyencapsulated in responses RAPDU2 and commands CAPDU2 when they aretransmitted in the RF channel, and encapsulated in HCP commands“EVT_SEND_DATA” when they are transmitted in the pipe P3 of the HCIinterface. The inversion program PINVP1 takes responsibility for theencapsulation of responses RAPDU1 in commands CAPDU2 and for thede-encapsulation of commands CAPDU1 present in the responses RAPDU2. Thecard RF gate CRFG2 takes responsibility for the encapsulation ofcommands CAPDU1 and of responses RAPDU1 in commands “EVT_SEND_DATA”.

End of Transaction Phase (EOT)

The transaction finishes by the sending of particular command CAPDU2 bythe passive reader RCIC or by the absence of the sending of a newcommand by it. The inversion program PINVP1 thus ensures the closing ofthe RF channel by asking the host processor HP1 to stop emitting thefield and addresses to the reader application CAPi the commands“EVT_CARD_DEACTIVATED” then “EVT_FIELD_OFF”. The pipe P3 is then closed(step <PIPE_CLOSE>).

In the preceding, an embodiment of the invention wherein the inversionprogram PINVP1 is executed by the host controller HC of the controllerNFCC has been described. In other embodiments, the inversion program maybe executed by another unit of the NFC device, for example a second hostprocessor HP2, which thus acts as an intermediary between the controllerNFCC and the host processor HP1. Such an embodiment will now bedescribed.

Inversion Program Executed by a Host Processor

FIG. 9 shows another embodiment of an NFC device according to anembodiment of the invention, integrated in a portable device HD. The NFCdevice comprises the controller NFCC, the host processor HP1, and asecond host processor HP2. The host processor HP2 is linked to thecontroller NFCC by a bus BS2, for example an asynchronous bus linkingUniversal Asynchronous Receiver Transmitter (UART) interfaces of thecontroller NFCC and of the host processor HP2. The host processor HP1 islinked to the controller NFCC by the bus BS1 described above, and to thehost processor HP2 by a bus BS3, for example an ISO 7816 bus. Theprocessor HP2 is for example a mobile telephone baseband processor andthe processor HP1 a secure processor, such as a SIM card processor.

The controller NFCC includes a contactless interface CLF equipped withan antenna coil AC1 and a host controller HC. It is assumed aspreviously, in a non-limiting manner, that the host processor HP1presents all the functionalities of a conventional NFC controller, inparticular that it may implement one or more RF technologies RFTi, andthat it is configured to activate a reader RF gate RRFG or a card RFgate CRFG1 to allow the host processors HP1, HP2 to execute readerapplications RAPi and card applications CAPi. It is also assumed thatthe host processors HP1, HP2 each include at least one card applicationCAPi and a reader application RAPi. Thus, the NFC device may conduct atransaction with a conventional contactless integrated circuit CIC byopening a pipe P1 between a reader application RAPi executed by the hostprocessor HP1 and a technology RFTi, or a pipe P4 between a readerapplication RAPi executed by the host processor HP2 and a technologyRFTi, by the intermediary of gates RAG and RRFG. It may equally conducta transaction with a conventional reader RD by opening a pipe P2 betweena card application CAPi executed by the host processor HP1 and atechnology RFTi, or a pipe P5 between a card application CAPi executedby the host processor HP2 and a technology RFTi, by the intermediary ofgates CAG and CRFG1.

Additionally, the host processor HP2 also includes a program inversionprotocol PINVP3 according to embodiments of the invention. Thisinversion program PINVP3 is configured to establish a communication witha passive reader RCIC according to an embodiment of the invention, bythe intermediary of a technology RFTi and of the interface CLF, receivefrom the passive reader RCIC commands CAPDU1, and communicate them tothe host processor HP1 as if they were commands received by a true NFCreader. It is also configured to receive from the host processor HP1responses RAPDU1 to such commands, and to supply them to the passivereader RCIC for treatment. To this end, the inversion program PINVP3 isconfigured to activate a reader application gate RAG and to request theHCI administrator to open a pipe P6 linking the gate RAG to a reader RFgate RRFG associated with a technology RFTi. The inversion programPINVP3 is also configured to activate a card RF gate CRFG2 and torequest from the HCI administrator the opening of a pipe P7 linking thecard RF gate CRFG2 to a gate CAG of a card application CAPi executed bythe host processor HP1.

FIG. 10 is an ensemble view of an architecture of an NFC device and ofthe passive reader RCIC allowing the card application CAPi of theprocessor HP1 to conduct a transaction with the passive reader RCIC, bythe intermediary of the processor HP2 and of the controller NFCC. Eachelement RCIC, NFCC, HP1, HP2 includes a physical layer PHL and a datalink layer DLL. A physical layer PHLa of the passive reader RCICcooperates with a first physical layer PHLb of the controller NFCC, thatis the interface CLF, to create an RF communication channel and toensure the transmission and the reception of data in the RF channel. Asecond physical layer PHLc of the controller NFCC cooperates with afirst physical layer PHLd of the host processor HP2 to ensure thetransmission of data on the bus BS2. The physical layers PHLc, PHLd are,for example, UART interfaces. A second physical layer PHLe of the hostprocessor HP2 cooperates with the physical layer PHLf of the hostprocessor HP1 to ensure the transmission of data on the bus BS2. Thephysical layers PHLe, PHLf are for example ISO 7816 bus interfaces.

Similarly, a data link layer DLLa of the passive reader RCIC cooperateswith a first data link layer DLLb of the controller NFCC, to form a datalink DLL1 ensuring the transport of data in the RF channel created bythe physical layers PHLa and PHLb, according to a technology RFTi (forexample of the Type A, B, B′, or F). A second data link layer DLLc ofthe controller NFCC cooperates with a first data link layer DLLd of thehost processor HP2 to form a data link DLL2 ensuring the transport ofdata between the controller NFCC and the host processor HP2. The datalink layers DLLc, DLLd comprise for example an asynchronous data linklayer and an HCI data link layer. Finally, a second data link layer DLLeof the host processor HP2 cooperates with a data link layer DLLf of thehost processor HP1 to form a data link DLL3 ensuring the transport ofdata between the host processor HP2 and the host processor HP1. The datalink layers DLLe, DLLf comprise for example an ISO 7816 data link layerand an HCI data link layer.

Finally, above the data link layers, the controller NFCC includes atechnology RFTi and a reader RF gate RRFG, the host processor HP2comprises the inversion program PINVP3, and the host processor HP1comprises a card application CAPi. The passive reader RCIC includes, aspreviously, the inversion program PINVP2 cooperating with the readerapplication emulation program RAEP.

The inversion program PINVP3 includes a function RAPL (sub-program)forming the equivalent of a reader application, to detect and establisha communication with the passive reader RCIC as a contactless integratedcircuit, by the intermediary of the controller NFCC. Thus, by means ofthe function RAPL, the inversion program PINVP3 configures the interfaceCLF in active mode to emit a magnetic field and establish an RF channelwith the passive reader RCIC according to a technology RFTi. Theinversion program PINVP3 then dialogues with the inversion programPINVP2 of the passive reader RCIC and addresses to it commands CAPDU2.It receives responses RAPDU2 emitted by the inversion program PINVP2within which are encapsulated the commands CAPDU2 supplied by theprogram RAEP. It de-encapsulates the commands CAPDU1 and communicatesthem to the card application CAPi of the host processor HP1 via the pipeP7 of the HCI interface. The inversion program PINVP3 then receivesresponses RAPDU1 emitted by the card application CAPi of the hostprocessor HP1, via the pipe P7 of the HCI interface. It encapsulatesthem in commands CAPDU2 that it sends to the passive reader RCIC via thepipe P6 of the HCI interface and the RF channel. The inversion programPINVP2 receives these commands, extracts from them the responses RAPDU1,and communicates them to the program RAEP for treatment, which thensupplies a new command CAPDU1 and so forth until the transaction isachieved.

FIG. 11 describes, in further detail, steps of a transaction between thehost processor HP1 and the passive reader RCIC. A detection phase (DET)of the passive reader RCIC, a transaction initialization phase (TINIT),a transaction phase as such (TRANSACTION), and an end of transactionphase (EOT) can be distinguished.

It is assumed in this implementation example that the inversion programPINVP3 is configured to detect itself the presence of the passive readerRCIC, via the function RAPL, by cyclically addressing HCI commands“EVT_READER_REQUESTED” to the controller NFCC. Nevertheless, thedetection phase of the passive reader RCIC could also be conducted by areader application of the host processor HP2, or even a readerapplication of the host processor HP1. In this case, the detection ofthe passive reader RCIC would cause the activation of the inversionprogram PINVP3.

Detection Phase (DET)

The detection phase thus includes the preliminary activation of theinversion program PINVP3 and the creation of the pipe P6 between theprogram PINVP3 and the controller NFCC, via a reader application gateRAG (Cf. FIG. 9), by steps “PIPE_CREATE, PIPE_OPEN”. Then, the inversionprogram PINVP3 regularly polls the surroundings of the NFC device bysending the command EVT_READER_REQUESTED to the controller NFCC. Whenthe passive reader RCIC is detected, the controller NFCC conducts RFcommunication channel initialization steps, and optionally ofanti-collision, and of activation of the integrated circuit (steps“INIT, ANTICOL”). The controller NFCC then sends to the readerapplication RAPi the command EVT_TARGET_DISCOVERED. The inversionprogram PINVP3 then addresses to the controller NFCC an applicationselection command “TagApplicationSelect”. The command is of the type(“CAPDU2[TagApplicationSelect]”) and is encapsulated in the commandWR_XCHG_DATA in the pipe P6. The command CAPDU2 is transferred by thecontroller NFCC to the passive reader RCIC via the RF channel. Thepassive reader RCIC sends back a particular response RAPDU2 containingan information “ReaderTagType” signifying that it forms a passivereader. As indicated above, this particular response RAPDU2 differs froma conventional contactless integrated circuit response. It may be aresponse containing a field SW1-SW2 different than that usually sentback by a contactless integrated circuit, for example SW1-SW2=9001h(hexadecimal notation), or a response containing a standard fieldSW1-SW2 of value 9000h and a determined data field signifying that theintegrated circuit is of the passive reader type. This particularresponse RAPDU is communicated to the inversion program PINVP3 by meansof the command WR_XCHG_DATA via the pipe P6.

Transaction Initialization Phase (TINIT)

The particular response RAPDU causes the inversion program PINVP3 toactivate the card RF gate CRFG2 as well as an associated registrycontaining parameters of the RF channel. As previously, the inversionprogram PINVP3 may set, in this registry, parameters of the RF channelthat do not correspond to those of the RF channel that was created bythe controller NFCC to access the passive reader RCIC.

The inversion program PINVP3 then requests the HCI administrator to openthe pipe P7 linking the gate CRFG2 to the gate CAG of the cardapplication CAPi of the host processor HP1 (steps “PIPE_CREATE,PIPE_OPEN”). The inversion program PINVP3 then sends the commandEVT_FIELD_ON to the card application CAPi to make it believe that an NFCreader emitting a magnetic field has been detected.

The initialization phase also includes the sending to the passive readerRCIC of a command CAPDU2 of the type CAPDU2[RequestforCAPDU] forming arequest for the supply of a reader application command CAPDU1. Theinversion program PINVP3 sends this command to the controller NFCC viathe pipe P6 by means of a command WR_XCHG_DATA and the host processorHP1 sends it to the passive reader RCIC. The passive reader RCICresponds by means of a response of the type RAPDU2(CAPDU1[SelAppX])within which is encapsulated a command CAPDU1. The command CAPDU1 is forexample a selection command of an application “X” to select (“SelAppX”).The response RAPDU2 containing the command CAPDU1 is transmitted to theinversion program PINVP3 via the pipe P6 in encapsulated form in acommand WR_XCHG_DATA. Upon reception of the response RAPDU2, theinversion program PINVP3 de-encapsulates the command CAPDU1, addressesthe command EVT_CARD_ACTIVATED via the pipe P7 to the card applicationCAPi, then addresses to it the command CAPDU1[SelAppX] encapsulated inthe command “EVT_SEND_DATA”.

Transaction Phase (TRANSACTION)

The transaction phase described above in relation with FIG. 10 includesthe exchange of commands CAPDU1 and of responses RAPDU1 between the cardapplication CAPi and the reader application emulation program RAEP. Moreprecisely, in response to the command CAPDU1[SelAppX] received at theend of the initialization phase, the card application CAPi sends back afirst response RAPDU1, then the reader application emulation programRAEP of the passive reader RCIC sends back a command CAPDU1, and soforth until the end of the transaction.

The commands CAPDU1 and the responses RAPDU1 are respectivelyencapsulated in responses RAPDU2 and commands CAPDU2 when they aretransmitted in the RF channel. The responses RAPDU2 and the commandsCAPDU2 are themselves encapsulated in commands WR_XCHG_DATA when theycirculate in the pipe P6 between the controller NFCC1 and the inversionprogram PINVP3. The responses RAPDU1 and the commands CAPDU1 areencapsulated in commands EVT_SEND_DATA when they circulate in the pipeP7 between the inversion program PINVP3 and the card application CAPi.The reader application gate RAG of the inversion program PINVP3 takesresponsibility for the encapsulation of commands CAPDU2 in commands“WR_XCHG_DATA” and for the de-encapsulation of responses RAPDU1 presentin the commands WR_XCHG_DATA. The inversion program PINVP1 takesresponsibility for the encapsulation of responses RAPDU1 in commandsCAPDU2 and the de-encapsulation of commands CAPDU1 present in theresponses RAPDU2. The card RF gate CRFG2 takes responsibility for theencapsulation of commands CAPDU1 and of responses RAPDU1 in commands“EVT_SEND_DATA” (FIG. 9).

End of Transaction Phase (EOT)

The transaction finishes by the sending of a particular command CAPDU2by the passive reader RCIC or by the absence of the sending of a newcommand by it. The inversion program PINVP3 thus ensures the closing ofthe RF channel by asking the host processor HP1 to stop emitting thefield, and addresses to the reader application CAPi the HCP commands“EVT_CARD_DEACTIVATED”, then “EVT_FIELD_OFF”. The pipe P7 between thegates CRFG2 and CAG is then closed (step <PIPE_CLOSE>).

Other Embodiments and Applications

It will clearly appear to the skilled person that embodiments of thepresent invention are susceptible of diverse applications. In a generalmanner, a passive reader RCIC is susceptible of being integrated in anytype of portable or fixed device. The terms “card”, “contactless chipcard”, or “tag” have the same signification and designate a supportequipped with a passive reader RCIC. A passive reader destined to beused as a reader and not as an integrated circuit of a contactless chipcard, is not necessarily integrated in a portable support and may bearranged in or on a fixed support, for example, payment gates or accesscontrol. Equally, even though such a passive reader has been presentedas a contactless integrated circuit, the term “contactless” designatesthe communication interface that a passive reader uses to exchange datawith the NFC device and does not in any way signify that the integratedcircuit cannot be equipped with contacts. The passive reader RCIC mayalso be realized by means of an integrated circuit called “combi”comprising both a contact communication interface (for example ISO 7816contacts) and a contactless communication interface.

Moreover, the term “passive” should not be interpreted as signifyingthat a contactless integrated circuit forming a passive reader accordingto the invention does not include any capability for emitting a magneticfield and/or that it does not emit any magnetic field during atransaction. Indeed, according to the operating principle of the cardemulation mode such as described by EP 1 327 222 (U.S. Pat. No.7,098,770), a passive charge modulation may also be emulated by shortduration emissions of the magnetic field, that are perceived by theentity emitting the principal field as charge modulation signals. Theterm “passive” therefore simply signifies that a passive reader RCICaccording to the invention does not emit the principal magnetic fieldthat allows the transaction to be conducted, as opposed to aconventional reader.

In addition, the term “transaction” may designate any type ofcommunication or of exchange of data, and does not exclusively designatea financial transaction or a transaction involving a payment.

In the preceding, embodiments of the invention have been described thatare compatible with the NFC Forum specifications as far as thecommunication interface between the NFC device and the passive readerRCIC is concerned, this compatibility being in particular ensured thanksto the encapsulation of commands and responses CAPDU1 and RAPDU1 inresponses and commands RAPDU2 and CAPDU2 circulating in the RF channel.Similarly, embodiments of the invention have been described that arecompatible with the ETSI specification concerning the communicationinterface between the controller NFCC and the host processor HP1 (firstembodiment), or concerning the communication interface between thecontroller NFCC1 and the host processors HP1, HP2 and between the hostprocessors HP1, HP2 themselves (second embodiment), thanks to the use ofHCI pipes and HCP commands. The invention may however be implemented ina different manner in applications where it is not necessary ordesirable to ensure the compatibility with such specifications. Thus, inembodiments of the invention, the passive reader RCIC may supplycommands CAPDU1 that are not encapsulated in responses RAPDU2 tocommands CAPDU2 sent by the NFC device and the controller NFCC1 may sendto the passive reader RCIC responses RAPDU1 that are not encapsulated incommands CAPDU2. Similarly, the inversion programs PINVP1 or PINVP3 maytransfer to the host processor HP1 commands supplied by the passivereader RCIC without encapsulating them in HCI commands. Equally, thecommands and the responses may not be in the APDU format and may haveany format that may be envisaged by the skilled person. In suchembodiments, a protocol is provided to distinguish on the one hand thecommands and responses (CAPDU2, RAPDU2) that allow for the management ofthe communication between the inversion program PINVP1 or PINVP3 of theNFC device and the inversion program PINVP2 of the passive reader RCIC,and on the other hand commands and responses (CAPDU1, RAPDU1) relativeto the transaction between the emulation program RAEP of the passivereader and the card application of the host processor HP1. This protocolallows the inversion program PINVP1 or PINVP3 of the NFC device and theinversion program PINVP2 of the passive reader RCIC to differentiatebetween the commands or the responses that are for them and the commandsor the responses that they must transfer to the higher-level programs,respectively the card application CAPi and the emulation program RAEP.

It will be appreciated by those skilled in the art that changes could bemade to the embodiments described above without departing from the broadinventive concept thereof. It is understood, therefore, that thisinvention is not limited to the particular embodiments disclosed, but itis intended to cover modifications within the spirit and scope of thepresent invention as defined by the appended claims.

1. A method of conducting a transaction between an NFC device and apassive contactless integrated circuit, the NFC device comprising an NFCcontroller coupled to a contactless communication interface, and atleast a first host processor comprising at least one card applicationprogram, the method comprising: providing, in the contactless integratedcircuit, at least one reader application emulation program configured tosupply first reader application commands and to treat first cardapplication responses; and by an intermediary unit of the NFC device:setting the contactless communication interface in an active modewherein the interface emits a magnetic field and establishes acommunication with the contactless integrated circuit, receiving, fromthe contactless integrated circuit, first reader application commandsand transferring the first reader application commands to the first hostprocessor, and receiving, from the first host processor, first cardapplication responses and transferring the first card applicationresponses to the contactless integrated circuit.
 2. The method of claim1, further comprising: providing, in the intermediary unit, a firstprotocol inversion program; providing, in the contactless integratedcircuit, a second protocol inversion program configured to cooperatewith the reader application emulation program; establishing, between thefirst and the second inversion programs, a contactless communicationwherein the intermediary unit acts as a reader relative to thecontactless integrated circuit; and by an intermediary of the second andthe first inversion programs: transferring to the first host processor,first reader application commands supplied by the reader applicationemulation program, and transferring to the reader application emulationprogram, first card application responses supplied by the cardapplication of the first host processor.
 3. The method of claim 1,further comprising, by the intermediary unit: receiving from the firsthost processor, first card application responses, encapsulating thefirst card application responses in second reader application commands,and transferring the second reader application commands to thecontactless integrated circuit; and receiving from the contactlessintegrated circuit, first reader application commands encapsulated insecond card application responses, de-encapsulating the first readerapplication commands, and transferring the first reader applicationcommands to the first host processor.
 4. The method of claim 1, whereinthe first reader application commands emitted by the reader applicationemulation program and the first card application responses emitted bythe card application program are in the APDU ISO 7816 format.
 5. Themethod of claim 3, wherein the second reader application commands andthe second card application responses are in the APDU ISO 7816 format.6. The method of claim 1, further comprising supplying to the first hostprocessor, by the intermediary unit, HCI interface commands that causethe first host processor to perceive that the first reader applicationcommands received from the contactless integrated circuit are emitted byan NFC reader in the active mode.
 7. The method of claim 1, furthercomprising recording in a registry at the disposal of the first hostprocessor, RF channel parameters that cause the first host processor toperceive that the first reader application commands received from thecontactless integrated circuit as having been emitted by an NFC readerin the active mode.
 8. The method of claim 1, wherein the intermediaryunit is a host controller of the NFC device.
 9. The method of claim 1,wherein the intermediary unit is a second host processor of the NFCdevice.
 10. A contactless integrated circuit of the passive typearranged or to be arranged on or within a fixed or portable support, thecontactless integrated circuit comprising an NFC reader emulationprogram, and is configured to supply first reader application commandsand to treat first card application responses received in response toreader application commands.
 11. The contactless integrated circuit ofclaim 10, further comprising: a protocol inversion program configured torespond to second reader application commands and to supply second cardapplication responses; and at least one reader application emulationprogram configured to supply the first reader application commands andto treat the first card application responses.
 12. The contactlessintegrated circuit of claim 10, configured to: receive first cardapplication responses encapsulated in second reader applicationcommands; and encapsulate, in second card application responses, firstreader application commands.
 13. The contactless integrated circuit ofclaim 11, configured to: receive first card application responses andsecond reader application commands in the APDU ISO 7816 format; and emitfirst reader application commands and second card application responsesin the APDU ISO 7816 format.
 14. An NFC device comprising: an NFCcontroller coupled to a contactless communication interface; a firsthost processor comprising at least one card application program andconfigured to treat first reader application commands and to supplyfirst card application responses; an intermediary unit to coordinate atransaction between the host processor and a passive contactlessintegrated circuit of the reader type, the intermediary unit beingconfigured to: set the contactless communication interface in an activemode where the interface emits a magnetic field; receive, by theintermediary of the contactless communication interface in active mode,first reader application commands emitted by a passive contactlessintegrated circuit of the reader type and transfer the first readerapplication commands to the first host processor; and receive first cardapplication responses supplied by the first host processor and transferthe first card application responses, by the intermediary of thecontactless communication interface in active mode, to the passivecontactless integrated circuit of the reader type.
 15. The NFC device ofclaim 14, wherein the intermediary unit is also configured to: emit, bythe intermediary of the contactless communication interface, secondreader application commands allowing for the management of acommunication with a passive contactless integrated circuit of thereader type; and receive, by the intermediary of the contactlesscommunication interface, second card application responses emitted by apassive contactless integrated circuit of the reader type.
 16. The NFCdevice of claim 14, wherein the intermediary unit is configured to:encapsulate, in second reader application commands, first cardapplication responses supplied by the first host processor and transmitthe second reader application commands by the intermediary of thecontactless communication interface; and receive, by the intermediary ofthe contactless communication interface, second card applicationresponses within which are encapsulated first reader applicationcommands, de-encapsulate the first reader application commands, andtransfer the first reader application commands to the first hostprocessor.
 17. The NFC device of claim 15, wherein the intermediary unitis configured to: transmit, by the intermediary of the contactlesscommunication interface, second reader application commands and firstcard application responses in the APDU ISO 7816 format; and receive, bythe intermediary of the contactless communication interface, second cardapplication responses and first reader application commands in the APDUISO 7816 format.
 18. The NFC device of claim 14, wherein theintermediary unit is also configured to supply, to the first hostprocessor, HCI interface commands that cause the first host processor toperceive the first reader application commands received from thecontactless integrated circuit as having been emitted by an NFC readerin the active mode.
 19. The NFC device of claim 14, wherein theintermediary unit is also configured to supply, to the first hostprocessor, RF channel parameters that cause the first host processor toperceive reader application commands received from a contactlessintegrated circuit as having been emitted by an NFC reader in the activemode.
 20. The NFC device of claim 14, wherein the intermediary unit is ahost controller of the NFC device.
 21. The NFC device of claim 14,wherein the intermediary unit is a second host processor of the NFCdevice.
 22. A portable device, comprising the NFC device of claim 14.23. A method of establishing a communication with an NFC device havingan NFC controller coupled to a contactless communication interface; andat least a first host processor having at least one card applicationprogram, the method comprising: providing a contactless integratedcircuit of the passive type arranged or to be arranged on or within afixed or portable support; and configuring the contactless integratedcircuit to supply the NFC controller with first reader applicationcommands and treat first card application responses received from theNFC controller in response to reader application commands.
 24. Themethod of claim 23, comprising providing, in the contactless integratedcircuit: a protocol inversion program configured to respond to secondreader application commands from the NFC device and to supply the NFCdevice with second card application responses; and at least one readerapplication emulation program configured to supply the first readerapplication commands and to treat the first card application responses.25. The method of claim 23, comprising: with the contactless integratedcircuit, receiving first card application responses encapsulated insecond reader application commands; and with the contactless integratedcircuit, encapsulating, in second card application responses, firstreader application commands.
 26. The method of claim 23, wherein firstcard application responses, second reader application commands, firstreader application commands and second card application responses are inthe APDU ISO 7816 format.